Configuring DNS into an MC/Servcie Guard package

[Virginia Borraz]

Hi,

Has anyone configured a DNS into an MC/service Guard package ? If so, how have you do it ?

[Sridhar Bhaskarla · Accepted solution]

I haven't done it. But I guess it shouldn't be a problem.

1. Make sure you use floating IP and the hostname(alias) of the DNS servers on the clients.
2. Make the file system that has the name server database files sharable between the systems.
3. Take care of starting and stopping named in your control script.
4. Most importantly keep /etc/hosts on both the systems sync'ed and use as the key file for your name server database file build. And make the lookup policy in "hosts DNS" order. Otherwise during the failover situation, the systems may hang.

Just a guess.

-Sri

[melvyn burnard]

yes it has been done and does work.

[Christopher Caldwell]

While the previous answer is correct, I'm not sure why you'd put DNS in Service Guard, since DNS already has the concept of reliability and availability built in.

If you have two servers: one you can fail to and one that runs the DNS normally, the optimal configuration would be to run DNS on both servers all the time.

Assuming you advertise both DNS servers to your clients, DNS will do the right thing if one of the servers becomes unavailable.

[Uday_S_Ankolekar]

Hi,

You can Configure Secondary DNS server(s) for this. In case primary fails for some reason secondary takes the responsibilty of Primary DNS server.

Good Luck,
-USA..

[Sanjay_6]

Hi Virginia,

I guess if you really want to configure DNS as a SG package you can do that, but it is of no use. You configure secondary DNS server to fall back to in case the primary goes back. Moreover you would be wasting disk space and VG when you want to configure DNS as SG packge. Here is a thread from ITRC on how to configrue DNS. It does not need a lot of disk space and system resources,

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=4f200e8206fb5bfdbc/screen=ckiDisplayDocument?docId=200000045204865

Hope this helps.

Regds

[G. Vrijhoeven]

Hi,

It is possible since we have it running. The comments the others made about secondary DNS are valid. But one of the reasons for a big cluster is to get rid of multiple normal servers.

ps. mind the resolv remark.
IP adress/hostname of the package you put the DNS server in are static so that is not an issue.

Hope this will help.

Gideon